You can use either combo(carrot is better since you can actually get kizaru chain buff final stage) Betty will give her own weak chain buff so i dont recommend her for either team
I still haven't cleard a SINGLE grand voyage yet lol... always at least 1 unit missing, now it's ace yamato. Either a legend is missing, a bunch of support key units I can't get or another unit even if that ones farmable mostly not possible to get rn or any time soon cause either it was from kizuna or a time gated stage from the past in some shape or form. what a struggle. I think I hate supports the most in this game